<?php
$db=new PDO('mysql:host=localhost','root','12qwas');
$r=$db->exec('create database if not exists db3');
$r=$db->exec('use db3');
$r=$db->exec('create table if not exists students(xh varchar(9) primary key, name varchar(50), age int default 0)');
$r=$db->exec("delete from students where xh='233110240'");
var_dump($r);
$db->exec('truncate table students');
$r=$db->exec("insert into students(xh,name,age) values('233110240','朱',19),('233110225','田',88)");
var_dump($r);
$r=$db->exec("update students set name='张三风' where xh='233110240'");
var_dump($r);
